1. Field of the Invention
The present invention relates generally to a method and apparatus for providing mobile Internet Protocol Television (IPTV) service over heterogeneous wireless communication systems, and, more particularly, to a handover method and apparatus for providing mobile Internet Protocol Television (IPTV) service over heterogeneous wireless communication systems.
2. Description of the Related Art
Recently, due to the rapid growth of wireless communication technology, the demand for a variety of services using wireless communication technology, such as mobile IPTV service, is rapidly increasing. Meanwhile, mobile IPTV service must be provided in an environment in which a variety of existing mobile communication networks, such as a Wireless Local Area Network (WLAN), an IEEE 802.16 network and a 3GPP network, are working in conjunction with each other due to the characteristics of a wireless environment.
Currently, a variety of mobile communication networks, such as a WLAN, an IEEE 802.16 network and a 3GPP network, are provided. In order to provide efficient mobile IPTV service, the service must be provided seamlessly over a variety of communication networks.
Furthermore, in a wireless environment such as the environment of a mobile communication network, handover frequently occurs due to the mobility of a wireless terminal. Furthermore, due to the mobility of a terminal, not only handover within the same wireless network but also handover between heterogeneous networks must be performed.
Accordingly, mobile communication networks for supporting mobile IPTV service, handover between heterogeneous networks as well as handover within the same wireless network must be achieved.
In order to perform handover between different networks, that is, heterogeneous networks, as described above, a terminal must be equipped with one or more heterogeneous network interfaces and offer Quality of Service (QoS) and seamless service between wireless networks having different specifications.
Furthermore, in handover for wireless IPTV, a system must take into consideration the mobility of a terminal and the continuation of service between heterogeneous networks, and effective mobility management technology is required to provide stable service.
Such effective mobility management technology requires the provision of seamless handover between various types of wired and wireless networks. Accordingly, when a terminal using mobile IPTV service moves, effective mobility management technology enables seamless service to be provided by allowing a service user to continuously use data and a session being used over a serving access network over a target access network.
Mobile IPv6 (MIPv6), which is a next-generation Internet support technology, was developed to provide mobility. However, MIPv6 is a protocol simply related to the registration of the locations of an MN and the resetting of a path for the data packets of a current session. Since this protocol requires considerable delay time to detect the movement of a mobile node, configure the address of the MN and register the location of the mobile node, it cannot support real-time communication level mobility.
The Fast Handovers for Mobile IPv6 (FMIPv6) protocol similar to the above method was proposed more recently. However, in the FMIPv6 method, the exchange of signaling messages required for a mobile node to search for and identify an Access Router (AR) before handover, that is, during preparation for handover is necessary.
Due to the above procedure, the FMIPv6 method has problems in that delay occurs due to the exchange of signaling messages required to search for and identify an AR, so that the probability of operation in reactive mode is increased.
Furthermore, in the FMIPv6 method, when the mobile node operates in reactive mode, the mobile node retransmits a Fast Binding Update (FBU) message and receives a Fast Binding Acknowledgement (FBAck) message again.
As described above, in the FMIPv6 method, the reactive mode has the problem of causing handover delay time due to the retransmission of a message and the problem of requiring additional use of system resources as in the case of the transmission of a message.